Audio jacks, also referred to as phone connectors, phone jacks, or jack plugs, are typically used in connector assemblies for carrying audio signals. Dating back to the late 1800's, the audio jack is one of the oldest electrical standards still in existence. The audio jack is the preferred connector for use in the music industry based upon a 6.35 mm (4 inch) plug diameter, which provides a robust assembly that can be reused indefinitely.
The size of the audio jack makes it easy to grasp without tools, and it cannot be bent if stepped upon or otherwise used in a manner expected of insertion and removal. For this reason, the audio jack is the preferred connector for use with electric guitars, microphones, speakers, amplifiers, line levelers and like equipment found in the music industry, primarily audio signal transmission. The audio jack is cylindrical in shape having two, three or four contacts.
Unique to the audio jack is the amount of surface area that is provided by a cylindrical plug. However, the connector to which the plug engages is typically a single prong having a single point of contact. The single point of contact can become problematic, as it needs to press against the plug in order to create a connection. The greater force the contact imparts upon the plug, the better the electrical connection; however the higher stress placed upon the connector, can cause the ground connector to be off center and lose contact. If the electrical contact is de minimus, the ability to transfer an electrical signal is reduced. The conventional electrical contacts employed to engage the plug provide very little contact surface, which results in poor audio quality.
Numerous attempts have been made to improve upon the audio jack. U.S. Pat. No. 7,874,855 describes an audio jack connector having an insulating housing and a passageway. A contacting terminal is disposed on a side of the passageway having a holding portion and two contacting pieces slanted toward the same side separately from two opposite ends of the holding portion. A first fixing terminal, arranged on a side of the passageway, adjacent to the contacting terminal, has a first fixing slice. The first fixing slice has a side extended obliquely to form a first contacting piece connecting with one contacting piece. A second fixing terminal placed on an opposite side of the passageway has a second fixing slice, a second contacting piece obliquely connected with the second fixing slice for connecting with the other contacting piece. The contacting pieces are forced to slide on and depart from the first contacting piece and the second contacting piece when the contacting terminal is elastically pushed by the inserted plug.
U.S. Publication No. 2007/0232150 describes an audio jack connector including a housing and a set of contacts. The housing has a body, a mating portion extending from one end of the body, and an insertion hole defined in the mating portion and extending inwardly through the body along an axis direction. The set of contacts include signal contacts, a set of switching contacts disposed in the housing, and an exposed contact disposed at the outside of the housing. The switching contacts have a fixed contact and a movable contact. The mating portion of the housing has a cavity defined at an outer surface thereof for receiving a contacting portion of the exposed contact. The contacting portion has a propping block protruding outwardly beyond the outer surface of the mating portion.
U.S. Publication No. 2009/0298347 describes an audio jack connector that is suitable for selectively engaging with either a first multi-pole plug or a second multi-pole plug having more poles than the first multi-pole plug. Each of the multi-pole plugs has a plurality of poles insulated by insulating rings arranged thereinbetween. The audio jack connector includes an insulating housing having a chamber extending inward from a front thereof, and terminal groups. The terminal groups are disposed in the corresponding grooves and project into the chamber. When either of the first and the second multi-pole plugs is respectively inserted into the chamber, the terminal groups are against the multi-pole plug, wherein at least one of the terminal groups is against one of the insulating rings of the first multi-pole plug.
U.S. Pat. No. 6,220,899 discloses a connecting sleeve spring resiliently mounted in a connecting sleeve of an electrical connecting jack. The connecting sleeve spring has a arcuate sinusoid-like side profile, with its two ends curving in a direction opposite the curve of a center contact portion. The center portion has an inwardly angled tongue. When a plug having a collar is inserted into the electrical connecting jack, the collar comes in contact with the tongue and pushes the central contact portion inward, thus forcing the two ends of the connecting sleeve spring to move outward. The two ends press against the inner periphery of the collar.
U.S. Pat. No. 6,270,380 discloses a multipolar electrical connector that, as a counter connector 90, uses a single-head plug having a pole shaft in which center poles are disposed in plural positions in the axial direction, respectively (hereinafter, referred to merely as “multipolar connector”). In the invention, plural predetermined contact pieces are incorporated into the body, so that plural poles are ensured by the predetermined contact pieces. A required number of first additional contact pieces and second additional contact pieces are placed on the outer and inner peripheral sides of the boss portion, so that two or more poles are ensured by the additional contact pieces. According to the invention, therefore, the number of poles is increased by that of poles which are formed by the additional contact pieces.
U.S. Pat. No. 6,923,687 discloses an audio jack connector comprising a rectangular-shaped insulating housing, and a plurality of different contacts. The insulative housing has a base and a mating portion. A channel extends through the base and the mating portion. A front end of the channel defines a gap, and a number of receiving slits defined on the base at two sides of the channel, the base defining a depression communicating with the channel at a top wall thereof. A first and a second contact are received in the slits. A third contact mates with the top wall and comprises a mounting portion extending beyond the bottom wall of the insulative housing. A fourth contact is installed in a front end of the insulative housing and has an engaging portion extending through the gap and inserted into the front end of the channel for electrically connecting the mating plug connector.
U.S. Pat. No. 7,654,872 discloses an audio jack connector which includes a housing and a terminal group. The housing has an insertion hole extending inward from the front of the housing. The bottom of the base defines at least one signal terminal recess and an auxiliary terminal recess, a first aperture is defined in the bottom of the auxiliary terminal recess and communicates with the signal terminal recess. The terminal group has at least one signal terminal and an auxiliary terminal received in the signal terminal recess and the auxiliary terminal recess respectively. The signal terminal has a contact portion projecting into the insertion hole and an elastic portion extending from the end of the contact portion.
U.S. Pat. No. 7,785,119 discloses an audio jack connector having an insulating housing defining a rectangular base. The base has a passageway passing therethrough for receiving an inserted audio plug connector. A channel is formed at a top surface of the base for communicating with the passageway. A set of switch terminals mounted to the insulating housing comprise an elastic terminal and a fixing terminal. The elastic terminal has a first top plate and a switch arm extended outward from the first top plate, with a free end thereof projecting into the passageway through the channel. The fixing terminal has a second top plate disposed above the channel. The second top plate has a pair of cantilever switch slices extending toward each other and perpendicular to an extending direction of the switch arm, with free ends thereof suspended over the free end of the switch arm and spaced from each other.
U.S. Pat. No. 7,794,285 discloses an audio jack connector for receiving an audio plug connector which includes an insulating housing and a contact terminal. The insulating housing defines an insertion hole from a front end to a rear end thereof for receiving the audio plug connector and a recess communicating with the insertion hole. The contact terminal has a connecting portion received in the recess. Two opposite ends of the connecting portion are extended toward a same side to form a base portion and a first elastic arm. A first contact portion is protruded towards the base portion from a free end of the first elastic arm. A second elastic arm is bent towards the connecting portion from one end of the base portion. A second contact portion is protruded towards the first elastic arm from a free end of the second elastic arm. The first and second contact portions protrude into the insertion hole.
U.S. Pat. No. 8,801,476 discloses an electrical contact of an audio jack connector including a main portion, a soldering portion bending from a lateral edge of the main portion, an elastic portion extending curvedly from a distal end of the main portion to be located above the main portion. The elastic portion has a flexible beam, a first arm extending upwardly from the flexible beam and a second arm curvedly bending from the first arm. The first arm is consistent with a direction along which an audio plug connector is inserted. The second arm is adverse to a direction along which the audio plug connector is withdrawn.
U.S. Pat. No. 8,888,537 discloses an improved electronic audio receptacle connector which employs contacts that have multiple points of contact with a mating audio plug. The contacts each have multiple segments, each segment having a plurality of transverse fingers that interface with a conductive portion of the audio plug. The multiple points of contact improve the reliability of the receptacle connector. The housing of the receptacle connector may be made of two portions mated along an interface. The two portions may have features along the interface to impede moisture ingression and to interlock them together. U.S. Pat. No. D607,834 discloses an ornamental design for a contact of an audio plug connector.